How Pearls are Cultured

Woman in Pearl Jewelry
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Advances in aquaculture during these last 100 years have enabled man to perfect the science of pearling, or pearl farming. Having identified and successfully bred species of oysters with the best pearl-bearing qualities, scientists are able to encourage the production of pearls high in luster and uniform in color. This is the art of pearl culturing.

Successful pearl culturing demands an in-depth knowledge of mollusk biology. The overwhelming majority of pearls on the market today follow the same steps from start to finish – a process called nucleation. Technicians, many of whom apprentice for years to master their trade, must be careful and precise. A mistake or slip of the hand may reduce the quality of pearl or even kill a mollusk.

With great delicacy, a technician pries open the live mollusk and inserts a wedge to keep the shells just a couple centimeters apart. With exacting tools one might expect to find at their dentist, the technician then surgically implants a small irritant into the gonad of the mollusk. This is most often a polished piece of a donor mollusk’s shell. Another small strip of mantle tissue is inserted adjacent to the irritant. Then the mollusk is allowed to close.

This irritant is the nucleus around which the mollusk secretes layer upon layer of nacre, just as it does in the wild with a fabled grain of sand. The mollusk is only able to stand brief periods out of the sea, so very quickly it is returned to rest and heal. The mollusk then resumes its daily life of feeding and growing, all the while turning the foundations of a gem inside.

For years, typically 3 to 5 or even more, the mollusk nurtures the pearl within. Periodically the mollusk is culled from the sea and cleaned of the life and grime that affixes to its shell. When harvest is declared, the mollusks are lifted from the sea en masse and opened. On average, less than 3 percent of those cultivated will produce gem quality pearls. The pearls that emerge are then cleaned and sorted.

Pearl culturing is a patient process, but the result is sometimes nothing short of breathtaking.